fix(telegram): close source image handle in _compress_image_to_jpeg

Image.open() was never closed; convert()/resize() return new images so the
source file object lingered until GC (a real leak on Windows where the open
handle blocks later deletion of the original). Use the context manager.

plugins/platforms/telegram/adapter.py

@@ -4628,20 +4628,21 @@ class TelegramAdapter(BasePlatformAdapter):
             return None
 
         try:
-            img = Image.open(image_path)
-            if img.mode in ("RGBA", "LA", "P"):
-                # Alpha-capable modes: composite onto a white background so
-                # transparency doesn't render as black in the JPEG.
-                background = Image.new("RGB", img.size, (255, 255, 255))
-                if img.mode == "P":
-                    img = img.convert("RGBA")
-                if img.mode in ("RGBA", "LA"):
-                    background.paste(img, mask=img.split()[-1])
+            # Close the source handle before returning: convert()/resize() produce new images, so
+            # the original file object would otherwise stay open until garbage collection.
+            with Image.open(image_path) as src:
+                if src.mode in ("RGBA", "LA", "P"):
+                    # Alpha-capable modes: composite onto a white background so
+                    # transparency doesn't render as black in the JPEG.
+                    background = Image.new("RGB", src.size, (255, 255, 255))
+                    layer = src.convert("RGBA") if src.mode == "P" else src
+                    if layer.mode in ("RGBA", "LA"):
+                        background.paste(layer, mask=layer.split()[-1])
+                    else:
+                        background.paste(layer)
+                    img = background
                 else:
-                    background.paste(img)
-                img = background
-            elif img.mode != "RGB":
-                img = img.convert("RGB")
+                    img = src.convert("RGB")
 
             max_w, max_h = img.size
             max_dim = max(max_w, max_h)